As specified in a Long Term Evolution (LTE) protocol, user equipment (UE) needs to report a physical cell identifier (PCI) of a target cell to a serving base station (or a source base station) during a handover process. The serving base station determines the target cell based on the PCI of the target cell reported by the UE, and sends a handover instruction to implement cell handover. However, in an existing LTE system, there are limited PCI resources. The LTE system provides only 504 PCIs. Consequently, in actual application, different neighboring cells of a cell may share a PCI, that is, PCI confusion occurs. In this case, when the serving base station receives a PCI of a target cell reported by the UE, if the reported PCI is corresponding to a plurality of neighboring cells, the serving base station cannot select a correct target cell for the UE based on the PCI. In other words, the serving base station cannot correctly select, from the plurality of neighboring cells with the same PCI, the target cell to which the UE needs to be handed over.
In other implement, to resolve a PCI confusion problem of the UE in a handover process, the base station configures a parameter for the UE to read a cell global identity (CGI) of the target cell. Because a CGI can uniquely identify a cell, the base station can correctly select, from cells with a same PCI by obtaining the CGI of the target cell, the target cell to which the UE needs to be handed over.
However, CGI reading needs to be enabled for the UE by the base station after the UE reports a measurement report. Because additional signaling exchange is required, a cell handover delay is increased.